Created attachment 86731 [details]
Kernel log

Sometimes the X server crashes due to a GPU lockup, caused by a page fault. It
happens seemingly randomly, at irregular intervals (sometimes it takes several
hours, sometimes it crashes in half an hour).

Before that happens, I see a small amount of corruption (noise around the
cursor), then everything but the mouse hangs. After a while, the mouse also
hangs, the screen becomes black with a "_" symbol in the upper right corner of
the screen (but the mouse is still displayed), and after some more time the
whole screen becomes corrupt in vertical blocks. If I press Ctrl+Alt+F1 fast
enough, I can switch out of X and use the console for a while, otherwise the
whole PC hangs and I need to do a hard reboot.

This issue may or may not be related to bug #69029 (the symptoms seem similar,
but the errors are different).

I am using a GeForce 660 card on openSUSE 13.1 x86_64 Beta. I also reported the
bug downstream.